Police say several weeks ago, an 11-year-old boy returned to his Aspen Hill home to find his younger brother crying. His mother, Petrie, was cycling between fits of laughter and tears.

The 11-year-old went upstairs. A short time later, his mother appeared with a bow saw in her hand, asking why the boy wasn't working on his homework.

Petrie allegedly pinned her son in a kneeling position and "jammed" the teeth of the saw against the back of her son's neck, moving it back and forth.

The boy was able to escape the attack and gained possession of the saw. Petrie allegedly called her husband and admitted to attacking the boy.

Petrie's husband took her to a medical facility, where she told staff she felt "overwhelmed" and "was not doing enough to help her children with their autism." She worried that her sons would grow to be a "burden" on society and felt they "needed to die." Asked why she was at the hospital, Petrie stated she had "tried to kill her kids again."

Investigators met with the 11-year-old and noted "thin lines" and broken skin with "scabbing" on the boy's neck.

Defense attorney Sharon Diamant said Petrie had "absolutely no intent" to hurt anyone, has no criminal history and loves her children.

One neighbor described Petrie as a "lovely, stay-at-home mom" who was often seen ushering her children to events.

Were Petrie to be found guilty on all charges, she could face life in prison.